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%I #21 Oct 18 2021 08:40:12
%S 5,18,35,64,101,142,195,256,329,418,515,616,725,838,975,1124,1281,
%T 1454,1635,1828,2025,2254,2487,2728,2985,3254,3531,3812,4105,4418,
%U 4735,5072,5421,5774,6147,6536,6933
%N Sum of first n primes of form 4k+1.
%H Jianing Song, <a href="/A038346/b038346.txt">Table of n, a(n) for n = 1..10001</a>
%F a(n) = Sum_{k=1..n} A002144(k). - _Michel Marcus_, Oct 18 2021
%t Accumulate[Select[Prime[Range[100]],IntegerQ[(#-1)/4]&]] (* _Harvey P. Dale_, Jul 25 2011 *)
%o (PARI) a(n) = my(s=0); forprime(p=2, , if(p%4==1, s+=p; if(n--<1, return(s)))) \\ following _Charles R Greathouse IV_'s program for A078586
%Y Cf. A002144, A002313, A006278, A038347.
%K easy,nonn
%O 1,1
%A Den Roussel (DenRoussel(AT)webtv.net)
%E Offset corrected by _Jianing Song_, Oct 18 2021
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